Kirrkirr: A Java-based visualisation tool for XML dictionaries of Australian

LanguagesKevin Jansz

Department of Computer Science, University of Sydney, Australia

Dr. Christopher ManningComputer Science and Linguistics, Stanford University, USA

Dr. Nitin IndurkhyaSchool of applied Science, Nanyang Technological University, Singapore

Project ObjectivesAims of the project: examining the richness of lexical structure, in

particular the connotational and figurative use of words

providing innovative ways for representing a dictionary, through creative use of the medium of computers

augmenting dictionaries from corpora to be able to provide practical educationally useful

programs as a result (at low labor cost)

Main initial target: an interactive front end for exploring or using the Warlpiri dictionary.

Talk Outline The research agendas Kirrkirr: A Warlpiri dictionary browser The Lexical Database

– exploiting the strengths of XML

– indexing XML data

User interface and visualization User studies

Research Program: Lexicon A lexicon is not just words but a vast network of

associations between words and within and across the concepts represented by words

The aim of this work is to provide people with a better understanding of this conceptual map.

Traditional paper dictionaries offer very limited ways for making such networks visible

On a computer, one can imagine all sorts of ways of bringing out such relationships

MRD Structure The internal structures of current Machine Readable

Dictionaries usually merely mimic the structure of the printed form (Boguraev 1990)

Some work, notably WordNet (Miller 1995) has involved a fundamental rethinking of dictionary content and organization (here, organization via “synsets” which are related via links of part, subkind, opposite)

There has been little in the way of software to make them truly usable by different communities of users.

Initial focusKirrkirr: a Warlpiri browser

Warlpiri is an Australian Aboriginal language spoken in the Tanami desert (NW of Alice)

A computer interface for browsing the Warlpiri dictionary.

Rich lexical materials have been collected by linguists over decades (Hale’s fieldwork from 1959 on, MIT Lexicon Project in the 1980s)

Before Kirrkirr, results still haven’t been produced in a format usable by the community (only printouts)

Our educational goals There are a number of reasons for focusing on Warlpiri

for this electronic bilingual dictionary – There has been a large amount of research on Warlpiri creating one

of the most comprehensive lexical databases for any Australian Language

– There is a relatively large community of people interested in learning their traditional language

– The low level of literacy in the region makes an e-dictionary potentially more useful than a paper edition as it is less dependent on good knowledge of spelling and alphabetical order. Making it fun and easy to use is a considerable help as well.

Features such as being able to point and click, and hear the words take the emphasis away from knowing the written form of the word before the system is used

Target user community

Kirrkirr: A Warlpiri dictionary browser

(Jansz 1998; Jansz, Manning and Indurkhya 1999)

An environment for the interactive exploration of dictionaries.

Although our current work has just been with Warlpiri, the design is general (Arrernte coming soon!)

Attempts to more fully utilize graphical interfaces, hypertext, multimedia, and different ways of indexing and accessing information

Written in Java, it can either be run over the web [high bandwidth] or run locally (here Java’s main advantage is cross-platform support).

Specific goals An interactive environment that encouraged

exploration: easy and fun to use Reduction of the dependence on alphabetical order Catering to the needs of different user groups (kids,

teachers, professionals) Flexible enough to display appropriate information in

appropriate ways depending on user level

OverviewKirrkirr provides various modules Graph layout of word relationships Formatted dictionary entries Semantic domain browsing A notes facility for ‘jotting in the margin’ Multimedia: audio, pictures Advanced searching interfaces others in planning: formatting (XSL) editing, figuration

patterns

These attempt to cater to users with different competence levels

(Kirrkirr screen shot)

The lexical database Existing materials are stored in an ad hoc format of

markup using backslash codes with some (rather odd) nesting of structural tags

These were converted to XML using an error-correcting stack-based parser (written in PERL).– The inconsistency and flexibility of dictionary entries actually made

this a surprisingly difficult task.

– But parser tries to impose data integrity

Use of XML gives a clear structure to the data, and makes available many (free) tools

XML XML separates the structure of the data from its

presentation Much of the recent enthusiasm for XML has centered

around representing simple and rigid structures such as database records

The rich hierarchical and variable structure of dictionary entries is really more what something like XML excels at!

Result remains a portable, tangible text file

Alternative: a database The obvious thing for storing a lot of data Has clear advantages: structure, indexing, query

language, relationships, integrity. Many people have suggested using a database for

lexical data and some have actually done it (IITLEX, Austin and Nathan)

But in general lexicographers oppose the rigidity, and, in practice, standard relational databases are quite ill-suited to dictionaries

Problems with Relational Database

Dictionary entries vary enormously Data is fragmented Dictionaries are only loosely structured Same element can appear at many levels (dialect,

cross-reference, …) Database model is inflexible to extending the

dictionary structure Lessens portability

XML indexing - challenges Despite the various XML parsers available, it is

surprising that there has been little consideration in making single entries retrivable from the file

Present XML Parsers tend to put the entire XML document in memory (or some form of it) in memory, before the data extraction process begins

This is not practical when parsing significant XML databases (eg. the Warlpiri dictionary is approx. 10Mb).

XML Indexing - solutions The heirachial structure of XML lends itself to

indexing, as each separate entry in the XML file can be considered as a separate entity

To make the Warlpiri dictionary usable for Kirrkirr an ad hoc indexing system was developed– Uses a slightly modified Ælfred parser

– Entries are indexed by headword

The system returns an XML document object containing the single dictionary entry, facilitating– processing for related words (Graph layout)

– XSL processing to HTML

XML Indexing - solutions (2) The use of the XML indexing process considerably

improves effeciency as only requested entries are parsed, hence consering time and bandwidth– Once whole entries are parsed, they are kept temporarily in a cache

Thus the System uses XML as a median between the structure and indexing of a relational database, with the freedom and functionality of XML.

XML document

object

Kirrkirr

5

Kirrkirr’s XML Index ProcessIndex in Memory

XQL - Potential

Visualization of dictionary information

For applications with simple textual content behind them, there is little that can be done but an on-line reflection of a printed page

But we want more than just definitions of words: we want to know their relationships to other words, and the patterning in these relationships

In a computational approach, can mediate between the lexical data and the user

The interface can select from and choose how to present information (according to the user’s preferences) – in many different ways

Previous work Current systems present the search-dominated

interface of classic Information Retrieval systems: you type a word in a search box

Results try to mimic, but are generally inferior to, the printed version of the dictionary

Good feature: rapid searching These systems do little to utilize the captivating

qualities of computers: interactivity, user control and adaptability (Brown 1985).

Previous work (2) Only effective when user has a clearly specified

information need – even here, we are ignoring the distinction between information gained and knowledge sought (Sharpe 1995)

Lack browsing, and chances for incidental or curiosity driven learning

Lack tangibility and situatedness of paper: ineffective for getting an idea of a collection

We wish to exploit the essence of hypertext, which is “click to explore” browsing

Previous work (3) Little research work (in corpus linguistics,

visualization etc.) on dictionary visualization WordNet built a rich network of relationships, which

fundamentally departed from the paper dictionary tradition, and has been used in many computational projects

However very little has been done in the way of interfaces that make these relationships visible and intelligible to users.

Graphical representations seem particularly important given our target users.

Graph-based visualization There is a little previous work on graphical

representations of dictionaries For instance, the visual-thesaurus by plumbdesign

derived from WordNet But it is also a good demonstration of how chaotic

and confusing graphical interfaces can become.

Graph-based visualization

(Jansz 1998; Jansz, Manning and Indurkhya 1999) Classic graph layout problem Adapts work by Eades et al. (1998) and Huang et al.

(1998) on visualization and navigation of WWW document linkages

Uses the spring algorithm. Big advantage is that it is an iterative updating algorithm, and so gives an easy interactivity:– it wiggles and people can play with it.

Clarity and simplicity of graph: Software maintains a set of focus nodes to prevent overcrowding

Educational advantages Alphabetical order is important, but A web of words offers other effective opportunities for

learning A student can opportunistically explore words that are

related in various ways Important semantic relationships can be understood

Kirrkirr network display

Kirrkirr network display

Formatted dictionary entries Are produced automatically from the XML by using

XSL (James Clark’s XT) XSL allows easy modeling of some user preferences. Most trivially, one can leave out information such as

part of speech, or detailed definitions This is useful as many users find information

overload quite confusing and demotivating Can produce bilingual or monolingual dictionary Opportunities for various output styles, and formats

such as RTF or TeX for printing.

Formatted dictionary entries

Rich typology of link types The semantically rich types of linkages present in a

dictionary (synonym, antonym, hyponym, subheadword, variant, coverbs, …) solves one of the major problems of the web: we have many link types with a clear semantic interpretation

Use consistent color-coded text and edges to show these link types

Gives a richer browsing experience Can tell where you are going before clicking

Browsing Work (at PARC and elsewhere: Pirolli et al. 1996) has

stressed role for browsing as well as searching in information access

It provides a context for learning We provide browsing in several ways:

– conventional hypertext• but with rich semantically-interpreted links• their color-coding matches network edges

– network-based display of words– browsing through semantic domains

Such cultural information is hard to learn, and not normally in dictionaries or thesauri

Question: can terminology sets be derived automatically from appropriate corpora?

User study problems Since at present there is no dictionary available

except the printed out ‘database’ [complete with markup codes], it was hard for many people to judge the use of the interface, since there was no point of comparison.

First impressions only: It would have been good to let people try it out at their leisure, but unfortunately not possible (NT Ed all Macintosh, MRJ 2.1 shipping deadlines slipped past our study date…)

User studyMim Corris (Yuendumu, Willowra) User testing with primary and (lower) secondary

students Comments from teachers, other adults etc. Purely qualitative observational study of dictionary

use (Doing anything much else would be difficult.) Initial reactions are very enthusiastic Could use as a basis for classroom activities (better

with some further development: games and puzzles)

Conclusions Kirrkirr is just a prototype of what one can do to

visualize dictionaries We have addressed the challenge of making

dictionary information usable in the creation of an application which mediates between well-structured data and users’ needs for searching/browsing and presentation

While we have focused our research on Warlpiri, the system can be easily applied to other languages

Conclusions (cont.) “... The best future applications of MRDs in

education will be those most able to respond to the insights and needs of their users” (Kegl 1995)

Kirrkirr can be seen as a step towards the future of e-dictionaries